import math
class cirCle:
    S=0
    C=0
    def _init_(self,x,y,r)->None:
        self.x=x
        self.y=y
        self.r=r
    def C(self):
        self.C=math.pi*(2*r)
    def S(self):
        self.S=math.pi*(r*r)
cirCle1=cirCle(3,4,4)
print("圆的面积:",cirCle1.S)

